Abstract: Disclosed is a winding method using an air expansion structure, which accurately controls the winding process by preset inflation parameter values and preset winding parameter values, so as to create space for a membrane to contract after winding, that is, to relieve the stress of the membrane, so as to avoid the situation of deviation or innermost side wrinkling during winding of the membrane, and the rewinding procedure is not needed, so that the complexity of the working procedure is reduced.

Abstract: Disclosed are a ceramic and polymer compositely coated lithium ion separator and a preparation method therefor. The ceramic and polymer compositely coated lithium ion separator comprises a polyolefin porous membrane, a ceramic coating coated onto one or both sides of a membrane surface, and a polymer coating coated onto a ceramic surface or the membrane surface. The composite separator prepared in the present disclosure significantly enhances heat resistance of the separator and bonding strength thereof with positive and negative pole pieces, improves the wettability of an electrolyte, can effectively prevent an internal short circuit due to layer dislocation between the separator and the electrodes, and also improves hardness and safety performance of the battery.

Abstract: Disclosed are a ceramic and polymer compositely coated lithium ion separator and a preparation method therefor. The ceramic and polymer compositely coated lithium ion separator comprises a polyolefin porous membrane, a ceramic coating coated onto one or both sides of a membrane surface, and a polymer coating coated onto a ceramic surface or the membrane surface. The composite separator prepared in the present disclosure significantly enhances heat resistance of the separator and bonding strength thereof with positive and negative pole pieces, improves the wettability of an electrolyte, can effectively prevent an internal short circuit due to layer dislocation between the separator and the electrodes, and also improves hardness and safety performance of the battery.